Giovinco can be used in a 4-3-2-1 I think, which Allegri does like. Historically, I've seen him used a 4-3-2-1 and a 4-3-1-2. He also used a 4-3-3 in 2012-2013 with Stephen El Shaarawy, Niang and Pazzini I believe.
Giovinco could probably be suitable as the CAM in a 4-3-1-2 (he won't be marked by huge CBs), a left-sided withdrawn forward in a 4-3-2-1, or a winger in a 4-3-3.
I have a weird feeling Allegri will be more willing to use Pepe and Giovinco than Conte was.